The present invention relates generally to conveyor systems. More specifically, the present invention relates to a rod or grid-type conveyor belt.
Rod or grid-type conveyors comprise a series of longitudinally spaced, transversely extending rods which are interconnected at their ends as exemplified by commonly owned U.S. Pat. No. 4,036,352 issued to White on July 19, 1977. Endless conveyors of this type are used for the transportation of many goods or products, such as for cooling and proofing bakery goods, for example. The conveyor can be arranged in a double helix configuration in which the items travel upwardly along an outer helical flight and then downwardly along an inner helical flight, as disclosed in the above-mentioned White patent.
Rod-type conveyor belts are particularly useful in operations which utilize the circulation of air around the conveyed items, such as in the cooling of hot bakery goods, with the items being arranged side-by-side on the belt. However, such belts tend to sag under the weight of the conveyed items, which can result in a transverse sliding of the items. That is, when two items, such as two loaves of bread are disposed side-by-side on the belt, both loaves may have a tendency to converge towards the center of the belt as the belt sags. Such displacement can be undesirable in numerous respects. For example, certain items may become damaged upon being turned over or upon making contact with another item. Also, displacement of the items may interfere with the proper removal of the items. For example, a transfer system may be associated with the conveyor which removes one of the side-by-side items while re-cycling the other item. That is, the conveyor system may be such that the items on one side of the belt achieve a longer residence time in the conveyor system and are ready for removal while the items on the other side are to make another pass through the system. In that case, proper guidance of the items is made difficult if both items have shifted appreciably in the transverse direction. Heretofore, it has been necessary to provide a mechanism which senses the position of the items and attempts to displace one or both of the items back to a more suitable relationship, such as by a blast of air for example.
Another factor tending to displace the items on the belt is the effect of centrifugal forces created as the belt travels along a curved path.
It is one object of the present invention to overcome the above-enumerated problems.
Another object is to provide a rod-type conveyor belt which resists the tendency for side-by-side items to shift transversely.
A further object is to provide a rod-type conveyor belt which resists belt sag under the weight of the items being transported.
It is another object of the present invention to minimize item displacement caused by centrifugal forces.